/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.lsw.decoding;

import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.widget.TextView;

import com.google.zxing.ResultPoint;
import com.lsw.R;
import com.lsw.util.DensityUtil;
import com.lsw.util.DeviceUtil;
import com.lsw.util.DimenUtils;
import com.lsw.util.LogUtils;

import java.util.Collection;
import java.util.HashSet;

/**
 * This view is overlaid on top of the camera preview. It adds the viewfinder
 * rectangle and partial transparency outside it, as well as the laser scanner
 * animation and result points.
 * 自定义二维码扫描区域样式
 */
public final class ViewfinderView extends View {
    private Context context;
    private static final int[] SCANNER_ALPHA = {
            0, 64, 128, 192, 255, 192, 128, 64
    };
    private static final long ANIMATION_DELAY = 100L;
    private static final int OPAQUE = 0xFF;
    private static final int SPEEN_DISTANCE = 8;  //扫描线的下落速度
    private static final int MIDDLE_LINE_PADDING = 5;
    private static final int MIDDLE_LINE_WIDTH = 5;

    private final Paint paint;
    private Bitmap resultBitmap;
    private final int maskColor;
    private final int resultColor;
    private final int frameColor;
    private final int resultPointColor;
    private Collection<ResultPoint> possibleResultPoints;
    private Collection<ResultPoint> lastPossibleResultPoints;
    private boolean isFirst;
    private int slideTop;
    private int slideBottom;

    private Bitmap qrLineBitmap;//微信的扫描线是一张图片
    private int qrWidth;//扫描线的长
    private int qrHeight;//扫描线的高
    private Rect qrSrc;
    private Rect qrDst;
    //四个角对应的长和宽
    private int ScreenRate = 40, CORNER_WIDTH = 10;
    //文字画笔
    private Paint Textpaint;

    // This constructor is used when the class is built from an XML resource.
    //此构造方法是用来从xml文件中加载的时候调用的
    public ViewfinderView(Context context, AttributeSet attrs) {
        super(context, attrs);
        this.context = context;
        // Initialize these once for performance rather than calling them every
        // time in onDraw().
        paint = new Paint();
        Textpaint = new Paint();
        Textpaint.setColor(Color.WHITE);        // 设置颜色
        Textpaint.setStyle(Paint.Style.FILL);   // 设置样式
        Textpaint.setTextSize(DensityUtil.sp2px(context, 15));
        Resources resources = getResources();

        qrLineBitmap = BitmapFactory.decodeResource(resources, R.mipmap.qrcode_scan_line_yellow);
        qrWidth = qrLineBitmap.getWidth();
        qrHeight = qrLineBitmap.getHeight();
        qrSrc = new Rect(0, 0, qrWidth, qrHeight);

        maskColor = resources.getColor(R.color.viewfinder_mask);
        resultColor = resources.getColor(R.color.result_view);
        frameColor = resources.getColor(R.color.viewfinder_frame);
        resultPointColor = resources.getColor(R.color.possible_result_points);
        possibleResultPoints = new HashSet<ResultPoint>(5);
    }


    @Override
    public void onDraw(Canvas canvas) {
        Rect frame = CameraManager.get().getFramingRect();
        if (frame == null) {
            return;
        }

        //初始化中间线滑动的最上边和最下边
        if (!isFirst) {
            isFirst = true;
            slideTop = frame.top;
            slideBottom = frame.bottom;
        }

        int width = canvas.getWidth();
        int height = canvas.getHeight();

        // Draw the exterior (i.e. outside the framing rect) darkened
        paint.setColor(resultBitmap != null ? resultColor : maskColor);
        canvas.drawRect(0, 0, width, frame.top, paint);
        canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
        canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);
        canvas.drawRect(0, frame.bottom + 1, width, height, paint);

        if (resultBitmap != null) {
            // Draw the opaque result bitmap over the scanning rectangle
            paint.setAlpha(OPAQUE);
            canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);
        } else {
            //绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE
            slideTop += SPEEN_DISTANCE;
            if (slideTop >= frame.bottom) {
                slideTop = frame.top;
            }

            qrDst = new Rect(frame.left, slideTop, frame.right, slideTop + qrHeight);
            canvas.drawBitmap(qrLineBitmap, qrSrc, qrDst, null);

            paint.setColor(frameColor);

            // draw rect  画扫描区域的四个直角
            canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate,
                    frame.top + CORNER_WIDTH, paint);
            canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH, frame.top
                    + ScreenRate, paint);
            canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right,
                    frame.top + CORNER_WIDTH, paint);
            canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right, frame.top
                    + ScreenRate, paint);
            canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left
                    + ScreenRate, frame.bottom, paint);
            canvas.drawRect(frame.left, frame.bottom - ScreenRate,
                    frame.left + CORNER_WIDTH, frame.bottom, paint);
            canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH,
                    frame.right, frame.bottom, paint);
            canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate,
                    frame.right, frame.bottom, paint);

            Collection<ResultPoint> currentPossible = possibleResultPoints;
            Collection<ResultPoint> currentLast = lastPossibleResultPoints;
            if (currentPossible.isEmpty()) {
                lastPossibleResultPoints = null;
            } else {
                possibleResultPoints = new HashSet<ResultPoint>(5);
                lastPossibleResultPoints = currentPossible;
                paint.setAlpha(OPAQUE);
                paint.setColor(resultPointColor);
                for (ResultPoint point : currentPossible) {
                    canvas.drawCircle(frame.left + point.getX(), frame.top
                            + point.getY(), 6.0f, paint);
                }
            }
            if (currentLast != null) {
                paint.setAlpha(OPAQUE / 2);
                paint.setColor(resultPointColor);
                for (ResultPoint point : currentLast) {
                    canvas.drawCircle(frame.left + point.getX(), frame.top
                            + point.getY(), 3.0f, paint);
                }
            }
            float text_len = Textpaint.measureText(context.getResources().getString(R.string.scan_tip));
            canvas.drawText(context.getResources().getString(R.string.scan_tip), ((DensityUtil.getScreenWidth(context) - text_len) / 2), frame.bottom + DensityUtil.dip2px(context, 50), Textpaint);
            // Request another update at the animation interval, but only
            // repaint the laser line,
            // not the entire viewfinder mask.
            postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top,
                    frame.right, frame.bottom);
        }
    }

    public void drawViewfinder() {
        resultBitmap = null;
        invalidate();
    }

    /**
     * Draw a bitmap with the result points highlighted instead of the live
     * scanning display.
     *
     * @param barcode An image of the decoded barcode.
     */
    public void drawResultBitmap(Bitmap barcode) {
        resultBitmap = barcode;
        invalidate();
    }

    public void addPossibleResultPoint(ResultPoint point) {
        possibleResultPoints.add(point);
    }

}
